By Richard Horgan Los Angeles (Knewz) — Siegfried, Roy or Tony. That would have been the Knewz.com short list if given the chance to name one of three Sumatran tigers recently added to the ranks of the ZSL London Zoo. But patrons who variously outbid all others for the privilege combined to produce Inca, for the female in the group, and Zac and Crispin for the two males. “Inca, Zac and Crispin are great names for these feisty cubs – now four-months-old and growing fast,” Zoological Society of London Zoo tiger keeper Martin O‘Sullivan said. “Inca loves her food and is always ready to defend a b…